Stabilized bituminous emulsion



lize the a'foresaidlig'min product as: a dispersing agent'lprimary'orseeondary) for a large variety of inat'erials andto attain the final object-of: an emulsion-pomprisirig-the-lighin product, aqueous alkali metai baseror ammonium base solution; and-the materials itisdesired to emulsif y Ifthe refined 'lignin product of the invention lis-used;

' asthe primary emulsifier, amounts rangingrrom' ahout=1 to percent by weight-of dry lignin pro-" duetloased' on finished emulsion are sum cient, whereas name-damn product is used iasthe stabilizenfor an emulsion already containing: a primary emulsifier (added or naturally cone tamed), amounts ranging from about 0.25 to x 5 percent-by weight based onfinishedemulsion are sumcient: I

N'umerous water insoluble substancesp suchrasi fats, '-;fatty oilspanimal and Vegetable =waxes,.min eral -waxes such as monta'n w'ax and paraffin wax; natural 'an-d 'synthetic resins; asphalt, pitch and mineral oilsoan-floeadvantageously emulsified daythe'method or this inven-ticns Mixtures of -bi-tu r men; ex gs; pitcher asphalt; with synthetic resins, e: a; allr'yd' or ureaiormaldehyd'e resins; can-also: be adv'antageously emulsified: by the method of this invention.

In stabilizingquick 'setting bituminous emulsions of the type-described in Montgomeriefl; S. Patent No. 1,643,675, the'quick-setting-emulsien' III is'preferablyformed separately"and"a dispersion of refir'ied lig nin-product in aqueous alkali metal: orrammonium lease-solution is then'added to con-- vert thequiek setting emulsion to a mixing emulsion. In producing emulsions 0f bituminous sub stanceswhichare-not capable Of forming Montgomeri'e emulsions,-'itis'= preferred to mix the bitu-= meuand-an aqueous alkali metal or ammonium lease dispersion of refiried-ligning product together to formthe emulsion;

Thefoll'owing'sp'ecific examples will serve to illustrate the "practice and the advantages of this invention? EXAMPLE I An aqueouslalkaline solution of the product obtained from sodablack'liquor bythe process-descrihed .in Industrial and Engineering Chemistry, vol. 32'; pages 1399 -1400 (1940)} said product be-. ingthereinafter. referredtoas Lignin M,. con.- sistingof. 1 part by weight of. Lignin M, .2 parts by weight of water 3,nd 1%' per cent by weight ofcaustic sodabased onthe alkaline solution; wasused tooproduce" ail-emulsion of :18.5 parts by weight of a /200 penetration asphalt derived from'ep'etroieumzoil-w The 'procedurewas as follows? The alkalineisolution -of Lignin M was placed in a mix pot and heated to 150-200 F.- The 1 20m penetration: asphalt} at a temperature of 200-240 F., was titrated into :the" alkaline solutionrand'themixture was-meanwhile agitated. After alllthe asphalt had heenadd'ecL-the mixture was thinned by; adding "water to produce" a r finis'hediemulsion having :the following formula :1

Tests were'imade om this emulsions with results as set-forth inz-Tabl'e lbelaowz Appearance after 1 week-1;

A quick-setting asphalt emulsiomwas-prepared inth'emannerset forth inzUnited States Patent No. 11731491" to Braun. Part of the emulsion'was left unstabillzed and'part of the emulsionwas Sta"- bilized with 1.0 per cent by weight based on total: 7

solids in thenemulsi'on. of. Lignin M, addedxto-the emulsionlin the form of a 33 (by weight) s0-' lution of Lignin in dilute (l /3%) aqueous caustic soda solution:

low:

Ta'hleII T Lignin-M Unstabillzed .r

- Stabilized Emulsion. Emulsion:

Residue 57:o%-.; 58.8%. Gementmixingtest Complete break 3 grams.

Dmulsifieation s EXAMPLE -I]1 Refined ligninvi products were prepared from: soda black liquonrbyvvariousi.method-s; asphalt; emulsions were-stabilized with. these products and the. emul'si'onsrwere submitted-totestse Details. of; these preparations, the. emulsions and-Lthe .emulsiomtestsiare'asiolldws:

Oile -sa;mplecofr thisiblaclc liquor was diluted :to 20%;;solidsza. Carbondioxide was. -passed;through' it unti'lathe pH:.was 8.0 (requiring about:4 hours) the :wassheateduto .1 20. Fxwhile being agitated andthe mixture wasi-thenzall'owed to cool to room:.temperaturezwhile.='being"agitated:1 The. mixture: was. then ;filtered= (With': suction on a Buchnerffunnel :the filtered precipitate was then; washed with: 0.5%" aqueous sulfuric acid and then large; amounts ofcoldwater'. The filter cake waszdriedr'at 230-- -F.- and ground-*to about passingzadOfi meshrsi-e've.

A seeond-sample'and a-third' sample were treated identically;=- except that in the second sample 10% aqueoussulfuric-aoid and-in the third sam ple= 10%/ aqueous acetie acid replaced the carbon dioxide;-

The lignin products ofvthethreesamples were very similar in appearance. Data on thesame are given in Table III below? These lignin products were usedto stabilize .a quick-breaking asphalt emulsion (58% asphalt contentX'J In .eaeh:.case;:the digninz'product twas dispersed in caustic soda solution (one r'partlignm Tests were made orrthese emulsions withresultsas set forth inTable -II be" product in 3.7 parts of 0.7% aqueous NaOH) and the quantity of lignin product taken was equal to 1% of the weight of finished emulsion. A small amount (0.3% of finished emulsion) of boric acid was also added to adjust the pH of the emulsion. Test results were as follows:

EXAMPLE IV Lignin products were prepared as follows from the same black liquor as in Example III:

Sample I was prepared by treating the black liquor with 10% aqueous sulfuric acid solution to a pH of 8.0 and allowing the mixture to stand 30 minutes without heating or agitation. The precipitate was filtered on a Buchner funnel and dried without washing. The filtration was difiicult to accomplish because the precipitate had not been digested with the mother liquor but, nevertheless, it was capable of filtration. The yield of filter cake was 35.1% based on the black liquor.

Sample II was similarly prepared but the filter cake was washed repeatedly with large quantities of cold water. Yield of washed filter cake was 13.9% based on the black liquor,

Sample III was prepared by treating the'black liquor with 10% aqueous sulfuric acid solution to a pH of 5.5. The precipitate was recovered and washed as in the case of Sample II. Filtration and washing were more easily accomplishedthan in the case of Samples I and II. However, whereas Samples I and II would dissolve completely in dilute aqueous caustic soda solution, Sample III would not dissolve completely therein. lhe yield of Sample III was 30.3% based on black liquor.

Each of these samples was used to stabilize a quick-breaking asphalt emulsion (same as in Example III). In each case, the lignin sample was first dispersed in caustic soda solution (one part lignin sample in 2.1 parts of 1% aqueous NaOH) and the quantity of lignin sample used was 1% of the weight of finished emulsion. A small amount (0.3% of the finished emulsion) of boric acid was also added to the emulsion to adjust pI-I. Test results are given in Table V below, along with test results for Lignin M (which was used in the same manner as the other lignin I Fine shot on sieve.

The tests referred to in Tables I, II, IV and V were as follows:

8 Residue.The standard ASTM D244-40 distillation was employed, in which asphalt emulsion is distilled under prescribed conditions and the weight of residue is calculated and expressed as percentage of the original sample of emulsion.

Cement mixing test.The tentative ASTM D244-41T cement mixing test was employed, in which asphalt emulsion is mixed with Portland cement, the mixture passed through a sieve, and the amount of material retained on the sieve is determined. This should not exceed 5 grams.

DemuZsification.-The standard ASTM D244-40 demulsibility test was used, in which asphalt emulsion is mixed with 0.1 N CaClz solution, the mixture passed through a sieve, and the weight of retained material is determined. The percentage'demulsibility is the proportion (in per cent) of asphalt in the emulsion retained as residue on the sieve. or a full mixing emulsion (for mixing with soil and the like), the demulsibility should not exceed 2%, while for mixing with coarser aggregate, a higher demulsibility is permissible.

Sieve test.The standard ASTM D244-40 sieve test was employed, in which asphalt emulsion is poured through a sieve and the residue on the sieve is determined. The percentage residue, based on the emulsion, should not exceed 0.1%.

Viscosity.--The standard ASTM B24440 viscosity test was employed.

SettZement.The standard ASTM B24440 settlement test was employed, in which portions of asphalt emulsion are allowed to stand 5 days, small portions of emulsion are taken-oil from the top and bottom of the body of emulsion, and the numerical difierence between the percentage asphalt residue in the top portion and the percentage asphalt residue in the bottom portion is determined. This numerical difference is the settlement value, and it should not exceed 3%.

Dehydration-100 cc. of asphalt emulsion are placed in a cylindrical glass container having a fiat bottom, a diameter of millimeters and a depth of 40 millimeters. The container is placed in the center of a metal pan 5" in diameter and is surrounded by 50 grams of dry flake calcium chloride spread out in the pan. The entire assembly is kept in an oven at F. and at the end of 96 hours the glass container is removed, calcium chloride is wiped from its sides, and it is weighed. The percentage of water lost from the emulsion is calculated, and is expressed as a fraction of the original water content. It is desirable that this fraction (the dehydration value) be as high as possible, to promote rapid drying of the emulsion.

It will be seen, therefore, that the refined lignin products hereinabove described are capable of acting as primary emulsifiers (Example I) and as stabilizers for quick-setting emulsions (Examples II, III and IV) Regarding the various lignin products of the invention, the following general conclusions may be drawn: The preferred products, obtained by acidification of the black liquor to a pI-Iof about 7.8 to 9, followed by digestion of the precipitate with the mother liquor and washing with a weak aqueous solution of acid, such as sulfuric acid,

and copious quantities of water to free the pre' cipitate substantially completely of water-soluble products, are superior to products in. which the digestion or washing steps are omitted. Thus, the preferred products contain less water-soluble matter, they dissolve more nearly completely in dilute aqueous alkali than some of the other products, they produce emulsions having higher dehydration figures and emulsions containing them are less likely to contain shot. However, the somewhat inferior lignin products in which digestion and/or washing steps are omitted, or the pH is carried below 7,8. are nevertheless operative to produce good mixing emulsions.

Although the refined lignin product described, in the presence of an aqueous alkali metal or ammonium base solution, serves alone as an emcient emulsifying agent and emulsion stabilizer, its action may be improved by methods well known in the art. Thus, referring to Example II, it will be seen that the dehydration value of the unstabilized emulsion was only 0.30 while that of the Lignin M stabilized emulsion was 0.52. However, for many purposes it is desirable to have a dehydration value of 0.6 or more. This can be readily accomplished by lowering the pH of the emulsion (1 .1 in the stabilized emulsion of Example II) to 9 or less, preferably by the use of a Weak acid such as boric acid or oxalic acid, but also by the use of a dilute solution of strong acid. By such means, dehydration values considerably above 0.6 can be obtained. Adjustment of pH also has the advantage of improving immediate mixing qualities of the emulsion. Colloidal clay, polyvinyl alcohol, starch, dextrin, agar and other substances which have the property of swelling in water may be advantageously added, usually in small amounts, preferably less than 1 per cent by weight of bitumen, to assist in suspending the refined lignin product of the invention. The refined lignin product may also be used in conjunction with other emulsifying agents and emulsion stabilizers, such as those mentioned hereinabove.

Herein and in the appended claims, the termemulsion includes dispersions of solids in liquids and liquids in liquids, and emulsifying agent and like terms include agents for producing and maintaining dispersions of solids in liquids and liquids in liquds. Also, the terms alkali metal base and ammonium base, as hereinabove explained, are intended to include, respectively, the water-soluble alkali metal hy droxides and alkaline salts, and ammonia and water-soluble substituted ammonium bases (such as methylamine, triethanolamine, etc.). The term soda black liquor refers to the liquor produced in the soda process of paper pulp manufacture.

I claim: e

1. A freely flowing, full mixing, non-fermentable, non-grainy oil-in-water type emulsion capable of mixture with fine aggregates without breakdown, comprising 50-70% by weight of water-insoluble, water-dispersible high molecular weight, thermoplastic organic material dispersed in 20-50% by weight of water and containing 0.25-10% by weight of a high molecular weight waste soda liquor derivative described as follows:

substantially insoluble in water, benzene, carbon lwes and other low molecular weight organic compounds.

2. The composition of claim 1 in which the organic material is bituminous.

3. The composition of claim 1 wherein the organic material is bituminous and the soda liquor derivative is insoluble in soda liquor at a pH of about 7.8 to about 9.

4. The composition of claim 1 wherein the organic material is asphalt present in an amount of about 55 to about 5. The composition of claim 1 further characterized in that the organic material is asphalt and the emulsion is alkaline.

6. The composition of claim 1 wherein the or-' ganic material is asphalt and the emulsion is alkaline having a pH of less than about 9.

7. A freely flowing, full mixing, non-fermentable oil-in-water type emulsion capable of mixture with fine aggregates without breakdown, comprising 50-70% by weight of water-insoluble, water-dispersible high molecular weight, thermoplastic, organic material dispersed in 20-50% by weight of water and containing 0.25-10% by weight of a high molecular Weight waste soda liqour derivative described as follows: substantially insoluble in water, benzene, carbon tetrachloride, ether, and 5.5-9.0 pH waste soda liquor: soluble in aqueous caustic solutions, diethylene oxide, phenols, acetone, ethyl alcohol: soda liquor derivative being substantially free of ash, alkali metal salts, hemicelluloses and other low molecular weight organic compounds, said soda liquor derivative being produced by passing a carbon dioxide-containing gas into soda black liquor to reduce the pH to about 7.8 to 9 and precipitate a solid, coagulating the precipitated solid by heating it mildly in the presence of the mother liquor, filtering the liquor and solid precipitate, washing the precipitate, treating it with a dilute solution of strong mineral acid and in amount slightly in excess of that required to neutralize the precipitate, and washing it substantially free from water-soluble matter.

PAUL E. McCOY.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 7 Re 15,944 Kirschbraun Nov. 11, 1924 2,132,607 Davis et a1 Oct. 11, 1938 2,228,976 Reboult Jan. 14, 1941 2,355,180 Remy -1 Aug. 8, 1944 said 'waste p 6, 9. w. H. NEWBOLD 2,481,331

ANTENNA ORIENTATION CONTROL SYSTEM I Filed Aug. 29, 1944 ATTORNEY 

